More: Gymnastics

Two-time Olympian Sam Mikulak and Rio alternates Ragan Smith and Ashton Locklear headline the P&G Gymnastics Championships, which will crown national champions live on NBC Sports and Olympic Channel: Home of Team USA this week.

Senior competition in Anaheim starts Thursday with the first half of the men’s meet on the Olympic Channel and streaming on NBCSports.com/live and the NBC Sports app.

Further coverage on NBCSN on Friday and Saturday and NBC on Sunday will also be streamed.

The event will crown new U.S. all-around champions for the first time in four years.

Simone Biles, champion every year from 2013 through 2016, is taking a break from gymnastics but is expected to resume training ahead of next season. It’s unknown when Biles might return to competition, though.

Her Final Five teammates — Aly Raisman, Gabby Douglas, Laurie Hernandez and Madison Kocian — are also not suiting up in Anaheim. All haven’t competed since Rio save Kocian, who moved to NCAA competition at UCLA.

Smith and Locklear were in Rio as replacement athletes in case of injury. Neither competed, but both returned this year with eyes on October’s world championships in Montreal, where there will be no team competition.

The U.S. men’s program has also seen major turnover. Olympic and world medalists Danell Leyva, John Orozco, Jacob Dalton and Jonathan Horton have all retired since Rio.

Two members of the Rio Olympic team are entered at P&Gs — Sam Mikulak and Alex Naddour — but neither is expected to factor into the all-around. Mikulak, the U.S. all-around champion the last four years, is coming back from a torn Achilles in February and may feature on one or two apparatuses.

Naddour specializes on pommel horse (where he won the Olympic bronze medal) and still rings.

The all-around could come down to Yul Moldauer and Akash Modi. Moldauer beat Modi at the American Cup in March, while Modi returned the favor at the NCAA Championships in April.